P53 protein in proliferation, repair and apoptosis of cells

Implications of p53 in mitochondrial dysfunction and Parkinson's disease

Purpose: To study the underlying molecular mechanisms of p53 in the mitochondrial dysfunction and the pathogenesis of Parkinson's disease (PD), and provide a potential therapeutic target for PD treatment.

Methods: We review the contributions of p53 to mitochondrial changes leading to apoptosis and the subsequent degeneration of dopaminergic neurons in PD.

Results: P53 is a multifunctional protein implicated in the regulation of diverse cellular processes via transcription-dependent and transcription-independent mechanisms. Mitochondria are vital subcellular organelles for that maintain cellular function, and mitochondrial defect and impairment are primary causes of dopaminergic neuron degeneration in PD. Increasing evidence has revealed that mitochondrial dysfunction-associated dopaminergic neuron degeneration is tightly regulated by p53 in PD pathogenesis. Neurodegenerative stress triggers p53 activation, which induces mitochondrial changes, including transmembrane permeability, reactive oxygen species production, Ca2+ overload, electron transport chain defects and other dynamic alterations, and these changes contribute to neurodegeneration and are linked closely with PD occurrence and development. P53 inhibition has been shown to attenuate mitochondrial dysfunction and protect dopaminergic neurons from degeneration under conditions of neurodegenerative stress.

Conclusions: p53 appears to be a potential target for neuroprotective therapy of PD.

Cadmium disrupts spermatogenic cell cycle via piRNA-DQ717867/p53 pathway

Cadmium (Cd) is a harmful environmental pollutant that disrupts public health, including respiratory, digestive, and reproductive systems. In this study, male rats were exposed to CdCl2 at a dose of 3 mg/kg by oral for 28 days to investigate the impact on spermatogenesis. Testis tissue samples were collected after sacrifice, and piRNA expression levels were measured using piRNA microarray and qPCR. PiRNAs, specialized molecules involved in spermatogenesis, were examined. CdCl2 exposure led to disrupted piRNA expression, particularly in piRNA-DQ759395 in rats. This piRNA was found to have a binding site with p53, and a similar piRNA-DQ717867 was discovered in mice. In GC-2spd cells, CdCl2 exposure increased piRNA-DQ717867 expression, which resulted in cell cycle arrest and abnormal expression of cell cycle-related proteins. The activation of p53-related pathways and disruptions in cell cycle regulation were also observed. Antagomir-717867 transfections and PFT-a pretreatment in GC-2spd cells supported the involvement of piRNA-DQ717867 in regulating cell cycle-related proteins. This study suggests that Cd exposure induces abnormal expression of piRNA-DQ759395 in rat testis and that piRNA-DQ717867 may regulate p53, causing cell cycle abnormalities in GC-2spd cells. These findings help understand the mechanisms of male reproductive toxicity caused by Cd exposure and emphasize the role of piRNAs in cell cycle regulation and male reproductive health.

MYC Oncogene: A Druggable Target for Treating Cancers with Natural Products

Various diseases, including cancers, age-associated disorders, and acute liver failure, have been linked to the oncogene, MYC. Animal testing and clinical trials have shown that sustained tumor volume reduction can be achieved when MYC is inactivated, and different combinations of therapeutic agents including MYC inhibitors are currently being developed. In this review, we first provide a summary of the multiple biological functions of the MYC oncoprotein in cancer treatment, highlighting that the equilibrium points of the MYC/MAX, MIZ1/MYC/MAX, and MAD (MNT)/MAX complexes have further potential in cancer treatment that could be used to restrain MYC oncogene expression and its functions in tumorigenesis. We also discuss the multifunctional capacity of MYC in various cellular cancer processes, including its influences on immune response, metabolism, cell cycle, apoptosis, autophagy, pyroptosis, metastasis, angiogenesis, multidrug resistance, and intestinal flora. Moreover, we summarize the MYC therapy patent landscape and emphasize the potential of MYC as a druggable target, using herbal medicine modulators. Finally, we describe pending challenges and future perspectives in biomedical research, involving the development of therapeutic approaches to modulate MYC or its targeted genes. Patients with cancers driven by MYC signaling may benefit from therapies targeting these pathways, which could delay cancerous growth and recover antitumor immune responses.

Selenium deficiency exacerbated Bisphenol A-induced intestinal toxicity in chickens: Apoptosis and cell cycle arrest mediated by ROS/P53

Bisphenol A (BPA) is a phenolic organic synthetic compound that is used as the raw material of polycarbonate plastics, and its safety issues have recently attracted wide attention. Selenium (Se) deficiency has gradually developed into a global disease affecting intestinal function via oxidative stress and apoptosis. However, the toxic effects and potential mechanisms of BPA exposure and Se deficiency in the chicken intestines have not been studied. In this study, BPA exposure and/or Se deficiency models were established in vivo and in vitro to investigate the effects of Se deficiency and BPA on chicken jejunum. The results showed that BPA exposure and/or Se deficiency increased jejunum oxidative stress and DNA damage, activated P53 pathway, led to mitochondrial dysfunction, and induced apoptosis and cell cycle arrest. Using protein-protein molecular docking, we found a strong binding ability between P53 and peroxisome proliferator-activated receptor γ coactivator-1, thereby regulating mitochondrial dysfunctional apoptosis. In addition, we used N-acetyl-L-cysteine and pifithrin-α for in vitro intervention and found that N-acetyl-L-cysteine and pifithrin-α intervention reversed the aforementioned adverse effects. This study clarified the potential mechanism by which Se deficiency exacerbates BPA induced intestinal injury in chickens through reactive oxygen species/P53, which provides a new idea for the study of environmental combined toxicity of Se deficiency, and insights into animal intestinal health from a new perspective.

MT1G Regulates c-MYC/P53 Signal to Inhibit Proliferation, Invasion and Migration and Promote Apoptosis in Colon Cancer Cells

INTRODUCTION

Colon cancer is a common and malignant cancer featuring high morbidity and poor prognosis.

AIMS

This study was performed to explore the regulatory role of MT1G in colon cancer as well as its unconcealed molecular mechanism.

METHODS

The expressions of MT1G, c-MYC, and p53 were assessed with the application of RT-qPCR and western blot. The impacts of MT1G overexpression on the proliferative ability of HCT116 and LoVo cells were measured by CCK-8 and BrdU incorporation assays. Additionally, transwell wound healing, and flow cytometry assays were employed to evaluate the invasive and migrative capacities as well as the apoptosis level of HCT116 and LoVo cells. Moreover, the activity of the P53 promoter region was assessed with the help of a luciferase reporter assay.

RESULTS

It was found that the expressions of MT1G at both mRNA and protein levels were greatly decreased in human colon cancer cell lines, particularly in HCT116 and LoVo cell lines. After transfection, it was discovered that the MT1G overexpression suppressed the proliferation, migration and invasion but promoted the apoptosis of HCT116 and LoVo cells, which were then partially reversed after overexpressing c-MYC. Additionally, MT1G overexpression reduced c-MYC expression but enhanced the p53 expression, revealing that the MT1G overexpression could regulate c-MYC/P53 signal. Elsewhere, it was also shown that c-MYC overexpression suppressed the regulatory effects of MT1G on P53.

CONCLUSION

To conclude, MT1G was verified to regulate c-MYC/P53 signal to repress the proliferation, migration and invasion but promote the apoptosis of colon cancer cells, which might offer a novel targeted-therapy for the improvement of colon cancer.

Transcriptomic analysis of the effects of the HPV18 E6E7 gene on the cell death mode in esophageal squamous cell carcinoma

Human papillomavirus (HPV) infection is one of the main causes of esophageal carcinoma (ESCA), and its carcinogenic mechanisms in ESCA require further investigation. E6 and E7 are HPV oncogenes, and their genomic integration is a crucial reason for the transformation of host cells into cancer cells. In order to reveal the role of oncogenes E6 and E7 in ESCA cells, the RNA-Seq raw data for HPV18-positive and -negative esophageal squamous cell carcinoma (ESCC) samples derived from the NCBI BioProject database were analyzed, and the differentially expressed genes were identified. Moreover, differentially expressed genes were enriched significantly in multiple cell death pathways, including apoptosis (cyclin-dependent kinase inhibitor 2A, plakophilin 1 and desmoglein 3), pyroptosis (gasdermin A, gasdermin C, NLR family pyrin domain containing 3, absent in melanoma 2, NLR family pyrin domain containing 1 and Toll like receptor 1) and autophagy (Unc-51 like autophagy activating kinase 1, adrenoceptor beta 2). Consequently, the effects of cisplatin-induced apoptosis and Hank's balanced salt solution-induced autophagy, and α-ketoglutarate-induced pyroptosis in the ESCC-expressing E6 and E7 cells were verified. Therefore, the expression of E6E7 may culminate in the inhibition of multiple cell death modes, which may also be one of the mechanisms of oncogene-induced carcinogenesis.

Synergistic effect of chrysin and radiotherapy against triple-negative breast cancer (TNBC) cell lines

PURPOSE

Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer, accounting for 20% of cases. Due to the lack of a molecular target, limited options are available for TNBC treatment. Radiation therapy (RT) is a treatment modality for the management of TNBC following surgery; however, it has a detrimental effect on surrounding healthy tissues/cells at a higher rate.

METHODS

We examined the effect of RT in combination with chrysin as a possible radiosensitizing agent in an MDA-MB-231 cell line as a model of a TNBC. The growth inhibitory effects of chrysin were examined using an MTT assay. Flow cytometry was performed to evaluate apoptosis and expression of hypoxia-induced factor-1α (HIF-1α). The protein expression of p-STAT3/STAT3 and Cyclin D1 was examined using western blotting. Real-time PCR determined apoptotic-related genes (Bax, BCL2, p53).

RESULTS

Treatment of MDA-MB-231 cells with chrysin in combination with RT caused synergistic antitumor effects, with an optimum combination index (CI) of 0.495. Our results indicated that chrysin synergistically potentiated RT-induced apoptosis in MDA-MB-231 compared with monotherapies (chrysin and/or RT alone). Expression of HIF-1α was decreased in the cells exposed to combinational therapy. The apoptotic effect of combinational therapy was correlated with increased Bax (pro-apoptotic gene) and p53 levels along with reduced expression of Bcl-2 (anti-apoptotic gene). Increased apoptosis was associated with reduced expression of Cyclin D1, p-STAT3.

CONCLUSION

These findings highlight the potential effect of chrysin as a radiosensitizer, indicating the synergistic anti-cancer effect of chrysin and RT in TNBC. Further investigation is warranted in this regard.

The role of truncated p53 isoforms in the DNA damage response

The tumour suppressor p53 is activated following genotoxic stress and regulates the expression of target genes involved in the DNA damage response (DDR). The discovery that p53 isoforms alter the transcription of p53 target genes or p53 protein interactions unveiled an alternative DDR. This review will focus on the role p53 isoforms play in response to DNA damage. The expression of the C-terminally truncated p53 isoforms may be modulated via DNA damage-induced alternative splicing, whereas alternative translation plays an important role in modulating the expression of N-terminally truncated isoforms. The DDR induced by p53 isoforms may enhance the canonical p53 DDR or block cell death mechanisms in a DNA damage- and cell-specific manner, which could contribute to chemoresistance in a cancer context. Thus, a better understanding of the involvement of p53 isoforms in the cell fate decisions could uncover potential therapeutic targets in cancer and other diseases.

The neuroprotective and neural circuit mechanisms of acupoint stimulation for cognitive impairment

Cognitive impairment is a prevalent neurological disorder that burdens families and the healthcare system. Current conventional therapies for cognitive impairment, such as cholinesterase inhibitors and N-methyl-d-aspartate receptor antagonists, are unable to completely stop or reverse the progression of the disease. Also, these medicines may cause serious problems with the digestive system, cardiovascular system, and sleep. Clinically, stimulation of acupoints has the potential to ameliorate the common symptoms of a variety of cognitive disorders, such as memory deficit, language dysfunction, executive dysfunction, reduced ability to live independently, etc. There are common acupoint stimulation mechanisms for treating various types of cognitive impairment, but few systematic analyses of the underlying mechanisms in this domain have been performed. This study comprehensively reviewed the basic research from the last 20 years and found that acupoint stimulation can effectively improve the spatial learning and memory of animals. The common mechanism may be that acupoint stimulation protects hippocampal neurons by preventing apoptosis and scavenging toxic proteins. Additionally, acupoint stimulation has antioxidant and anti-inflammatory effects, promoting neural regeneration, regulating synaptic plasticity, and normalizing neural circuits by restoring brain functional activity and connectivity. Acupoint stimulation also inhibits the production of amyloid β-peptide and the phosphorylation of Tau protein, suggesting that it may protect neurons by promoting correct protein folding and regulating the degradation of toxic proteins via the autophagy-lysosomal pathway. However, the benefits of acupoint stimulation still need to be further explored in more high-quality studies in the future.

Epinephrine facilitates the growth of T cell lymphoma by altering cell proliferation, apoptosis, and glucose metabolism

In recent years, studies have reported the role of stress-regulatory hormones, including epinephrine, in regulating the progression of a few cancers. However, the tumor-promoting action of epinephrine is not yet investigated in T cell malignancy, a rare and complicated neoplastic disorder. More so, very little is known regarding the implication of epinephrine in the glucose metabolic rewiring in tumor cells. The present investigation showed that epinephrine enhanced the proliferation of T lymphoma cells through up- and down-regulating the expression of PCNA, cyclin D, and p53, respectively. In addition, epinephrine inhibited apoptosis in T lymphoma cells possibly by increasing the level of BCL2 (an anti-apoptotic protein) and decreasing PARP level (a pro-apoptotic protein). Intriguingly, epinephrine is reported to stimulate glycolysis in T lymphoma cells by increasing the expression of crucial glycolysis regulatory molecules, namely HKII and PKM2, in a HIF-1α-dependent manner. Moreover, augmented production of ROS has been observed in T lymphoma cells, which might be a central player in epinephrine-mediated T cell lymphoma growth. Taken together, our study demonstrates that epinephrine might have a significant role in the progression of T cell lymphoma.

Proteomic Analysis of Protective Effects of Dl-3-n-Butylphthalide against mpp + -Induced Toxicity via downregulating P53 pathway in N2A Cells

BACKGROUND

Dl-3-n-butylphthalide (NBP) is an important medial therapy for acute ischemic stroke in China. Recent studied have revealed that NBP not only rescued the loss of dopaminergic neurons in cellular and animal models of Parkinson's disease (PD), but also could improve motor symptoms in PD patients. However, the protective mechanism is not fully understood. P53 is a multifunctional protein implicated in numerous cellular processes, including apoptosis, DNA repair, mitochondrial functions, redox homeostasis, autophagy and protein aggregations. In PD, p53 integrated with various neurodegeneration-related signals inducing neuronal loss, indicating the suppression of P53 might be a promising target for PD treatment. Therefore, the purpose of the current study was to systemically screen new therapeutic targets of NBP in PD.

METHOD

In our study, we constructed mpp + induced N2A cells to investigate the benefit effect of NBP in PD. MTT assay was performed to evaluate the cell viability; TMT-based LC-MS/MS was applied to determine the different expressed proteins (DEPs) of NBP pretreatment; online bioinformatics databases such as DAVID, STRING, and KEGG was used to construe the proteomic data. After further analyzed and visualized the protein-protein interactions (PPI) by Cytoscape, DEPs were verified by western blot.

RESULT

A total of 5828 proteins were quantified in the comparative proteomics experiments and 417 proteins were considered as DEPs (fold change > 1.5 and p < 0.05). Among the 417 DEPs, 140 were upregulated and 277 were downregulated in mpp + -induced N2A cells with NBP pretreatment. KEGG pathway analysis indicated that lysosome, phagosome, apoptosis, endocytosis and ferroptosis are the mainly enriched pathways. By using MCL clustering in PPI analysis, 48 clusters were generated and the subsequent KEGG analysis of the top 3 clusters revealed that P53 signaling pathway was recognized as the dominant pathway for NBP treatment.

CONCLUSION

NBP significantly relived mpp + -induced cell toxicity. The neuroprotective role of NBP was implicated with P53 signaling pathway in some extent. These findings will reinforce the understanding of the mechanism of NBP in PD and identify novel therapeutic targets.

Ophiopogonin D increase apoptosis by activating p53 via ribosomal protein L5 and L11 and inhibiting the expression of c-Myc via CNOT2

Ophiopogonin D (OP-D), which is extracted from the root tuber of Ophiopogon japonicus, is well known for its anti-inflammatory, anti-oxidant, and anti-cancer effects. It is also therapeutic for various diseases such as diabetic myocardial injuries, obesity, atopic dermatitis, and osteoporosis. However, there are insufficient reports on the anti-cancer effects and molecular mechanisms of OP-D in colorectal cancer. Therefore, this study aimed to investigate the anti-cancer-modulating effect of OP-D on colorectal cancer. The study proved that OP-D (20-40 uM) has significant cell viability inhibition and anti-proliferative effects in Cell Counting Kit-8 (CCK-8) assay and colony formation assay. In addition, our immunofluorescence analysis data showed that OP-D (40 uM) inhibited the expression of Ki67, a cell proliferation marker, and confirmed that OP-D could induce nucleolar stress by depletion of IPO7 and XPO1. Furthermore, our western blot data showed that OP-D induced p53 expression via ribosomal protein (RP) L5 or L11 and inhibited c-Myc expression through CNOT2 in a dose-dependent manner. Additionally, OP-D regulated cyclin D1 and CDK4, which are well known as cell cycle regulatory proteins. OP-D consistently inhibited the phosphorylation of AKT expression in a dose-dependent manner. Furthermore, OP-D shortened c-Myc's half-life in a time-dependent manner. Furthermore, CNOT2 knockdown enhanced the inhibitory effect of OP-D on c-Myc in colon cancer cells. Besides that, we confirmed that OP-D has a combinational anti-cancer effect of 5-FU or doxorubicin to reduce cell viability and induce apoptosis through p53 and c-Myc regulation. Altogether, our results suggest that OP-D regulates colon cancer cell proliferation and induces apoptosis by inhibiting c-Myc expression via activation of p53 and CNOT2 regulation. The study demonstrated that OP-D may be a promising natural anti-cancer agent for the treatment of colorectal cancer.

Integrative Analysis Reveals a Nine TP53 Pathway-Related lncRNA Prognostic Signature in Endometrial Cancer

Background

TP53 mutation is a common mutation gene in uterine corpus endometrial carcinoma (UCEC), and the TP53 signaling pathway plays an essential role in the tumorigenesis, progression, and immune infiltration in UCEC. We aimed to discover TP53 pathway-related lncRNAs in UCEC. Materials and methods. 528 UCEC patients with 587 transcriptional profiles were enrolled in this study. We first investigated the differential status of TP53 signaling pathway between tumor and normal tissues by GSEA analysis, then identified TP53 pathway-related lncRNAs, accordingly establishing a nine TP53 pathway related to the lncRNA signature in the training set and verified this signature in the test set. Besides, the interaction network was constructed; the immune infiltration, drug response to cisplatin and paclitaxel, and mutation atlas were investigated. Finally, we performed a subgroup analysis to check the universality of this signature.

Results

A nine TP53 pathway-related lncRNA prognostic signature was constructed and verified superior accuracy in predicting the overall survival of UCEC patients. Besides, high-risk patients showed a poor prognosis, but they were more sensitive to the cisplatin and paclitaxel. Notably, M2 macrophages were higher infiltrated in high-risk patients, and TP53 showed a significantly higher mutation in high-risk patients than low-risk patients.

Conclusions

We constructed and verified a nine TP53 pathway-related lncRNA prognostic signature in UCEC, which also contributes to the decision-making of the chemotherapy.

Grass carp (Ctenopharyngodon idella) DYRK2 modulates cell apoptosis through phosphorylating p53

In mammals, DYRK2 increases p53 phosphorylation level by interacting with it and then promotes cell apoptosis. However, the function of fish DYRK2 has not yet been elucidated. In this paper, we cloned and identified the coding sequence (CDS) of a grass carp DYRK2 (CiDYRK2) which is 1773 bp in length and encodes 590 amino acids. SMART predictive analysis showed that CiDYRK2 possesses a serine/threonine kinase domain. Subsequently, we used the dsRNA analog polyinosinic-polycytidylic acid (poly (I:C) and Grass carp reovirus (GCRV) to stimulate grass carp and CIK cells for different times and found that CiDYRK2 mRNA was significantly up-regulated both in fish tissues and cells. To explore the function of CiDYRK2, we carried out overexpression and knockdown experiments of CiDYRK2 in CIK cells. Real-time quantitative PCR (Q-PCR), TdT-mediated dUTP nick end labeling (TUNEL) assay and flow cytometry were used to detect the ratio of BAX/BCL-2 mRNA, the number of TUNEL positive cells, the proportion of Annexin V-positive cells respectively. The results showed that CiDYRK2 significantly up-regulated BAX/Bcl-2 mRNA ratio and increased the number of TUNEL-positive cells, as well as the proportion of Annexin V-positive cells. On the contrary, knock-down of CiDYRK2 significantly down-regulated BAX/Bcl-2 mRNA ratio in the cells. Therefore, CiDYRK2 promoted cell apoptosis. To study the molecular mechanism by which CiDYRK2 promoting cell apoptosis, subcellular localization and immunoprecipitation experiments were used to study the relationship between grass carp DYRK2 and the pro-apoptotic protein p53. The results showed that CiDYRK2 and Cip53 were located and co-localized in the nucleus. Co-immunoprecipitation experiment also showed that CiDYRK2 and Cip53 can bind with each other. We further found that DYRK2 can increase the phosphorylation level of p53. In a word, our results showed that grass carp DYRK2 induces cell apoptosis by increasing the phosphorylation level of p53.

Therapeutic restoring p53 function with small molecule for oncogene-driven non-small cell lung cancer by targeting serine 392 phosphorylation

p53 inactivation by disabling its function is a hallmark in lung carcinomas, emphasizing the significance of restoring p53 function as an attractive therapeutic strategy. However, the clinical efficacy of existing p53 activators is limited due to their inability to effectively activate p53 within the tumors. Here, we established a p53 activator screening assay in EGFR-driven lung cancer cells and identified a small molecular, MX-C4, as a promising candidate. Using high throughput compound screening and combination analyses, we found that MX-C4 effectively promoted the phosphorylation of p53 at serine-392 (s392). It exhibited potent antitumor activity in a variety of cancer cell lines, but only limited toxicity to NCI-H1299 (p53-null) and normal cell lines such as LX2 and HL-7702. Overexpression of p53 in NCI-H1299 cells by a p53 expressing virus vector sensitized cells to MX-C4 treatment, suggesting a p53-dependent anticancer activity. Furthermore, we demonstrated that MX-C4 bound to p53 and exerted its anticancer activity through cell cycle arrest at G2/M phase and apoptosis induction. Mechanistic study indicated that p53 activation regulated cell cycle and cell survival related targets at protein levels. Moreover, p53 activation raised phospho-p53 translocation to mitochondria and subsequently reorganized the Bcl-xl-Bak complex, thus conformationally activating Bak and inducing apoptosis. It is noteworthy that MX-C4 could effectively activate p53 within the tumors in EGFR-driven xenograft models, where tumor was significantly suppressed without obvious toxicity. Our study identified a promising candidate for lung cancer therapy by restoring p53 function.

A Novel ERK2 Degrader Z734 Induces Apoptosis of MCF–7 Cells via the HERC3/p53 Signaling Pathway

Breast cancer is one of the leading causes of death worldwide, and synthetic chemicals targeting specific proteins or various molecular pathways for tumor suppression, such as ERK inhibitors and degraders, have been intensively investigated. The targets of ERK participate in the regulation of critical cellular mechanisms and underpin the progression of anticancer therapy. In this study, we identified a novel small molecule, which we named Z734, as a new mitogen–activated protein kinase 1 (ERK2) degrader and demonstrated that Z734 inhibits cell growth by inducing p53–mediated apoptotic pathways in human breast cancer cells. Treatment with Z734 resulted in the inhibition of cancer cell proliferation, colony formation and migration invasion, as well as cancer cell death via apoptosis. In addition, the Co–IP and GST pulldown assays indicated that the HECT and RLD domains containing E3 ubiquitin protein ligase 3 (HERC3) could directly interact with ERK2 through the HECT domain, promoting ERK2 ubiquitination. We also observed a strong link between HERC3 and p53 for the modulation of apoptosis. HERC3 can increase the protein and phosphorylation levels of p53, which further promotes apoptotic activity. In a xenograft mouse model, the effect was obtained in a treatment group that combined Z734 with lapatinib compared with that of the single–treatment groups. In summary, our results indicated that Z734 actively controls the development of breast cancer through apoptosis, and HERC3 may mediate ERK2 and p53 signaling, which offers new potential targets for clinical therapy.

N-methyl-N-nitrosourea induces zebrafish anomalous angiogenesis through Wnt/β-catenin pathway

N-methyl-N-nitrosourea (MNU) is a prevalent environmental carcinogen, which leads to tumors in various organs in animal models, while the mechanisms involved were still not fully understood. It is well known that anomalous angiogenesis is a key step in tumorigenesis and progression. In this study, we found that MNU induced abnormal angiogenesis which was accompanied by upregulation of rspo1, p53 and vegfaa in zebrafish embryos. Moreover, it revealed that MNU-induced ectopic sprouting of blood vessels was significantly reduced in rspo1-knockdown but not p53-knockdown embryos, indicating that rspo1 was necessary for MNU-induced abnormal angiogenesis. Additionally, pharmaceutical activation or inhibition of Wnt/β-catenin signaling pathway using (2'Z,3'E)- 6-bromoindirubin-3'-oxime or CCT036477 significantly increased or inhibited the pro-angiogenic effect of MNU on developing zebrafish embryos, which was confirmed by the effect of proliferation and migration in MNU-treated bEnd.3 cells. These data together indicated that rspo1/Wnt/β-catenin/vegfaa axis is involved in the modulation of MNU-induced anomalous angiogenesis.

hnRNP E1 Regulates HPV16 Oncogene Expression and Inhibits Cervical Cancerization

hnRNP E1 (heterogeneous nuclear ribonucleoprotein E1) is an important RNA-binding protein (RBPs) that plays a vital role in tumor development. Human papillomavirus 16 (HPV16) contains numerous sites that can bind to RNA/DNA and may be modified by multiple RBPs, which contribute to HPV gene expression and HPV-associated cancer development. However, the effects of hnRNP E1 on HPV16 oncogenes in the development of cervical lesions remain unclear. A total of 816 participants with different grades of cervical lesions were enrolled in a community-based cohort established in Shanxi Province, China. The Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases were used to analyze the association between hnRNP E1 mRNA expression and cervical lesions. Cells with up_ and down_regulated hnRNP E1 were established. hnRNP E1 functions were evaluated using cell counting kit-8, flow cytometry analyses, and chromatin immunoprecipitation sequencing. Our results showed that hnRNP E1 expression was linearly dependent on the severity of the cervical lesions. Low expression of HPV16 E2, high expression of E6, and a low ratio of E2 to E6 could increase the risk of cervical lesions. hnRNP E1 expression was correlated with HPV16 oncogene expression. hnRNP E1-relevant genes were involved in the dopaminergic synapses, Wnt signaling pathway, gnRH secretion, and mTOR signaling pathway. hnRNP E1 significantly inhibited cell proliferation, induced apoptosis, arrested the cell cycle at the G0/G1 stage, and decreased HPV16 E6 expression. Our results indicate that hnRNP E1 could downregulate HPV16 E6 oncogene expression and inhibit cervical cancerization, which sheds new light on preventing the carcinogenicity of HPV across a range of diseases by regulating RNA-binding proteins.

Novel Insight into the Potential Role of Acylglycerophosphate Acyltransferases Family Members on Triacylglycerols Synthesis in Buffalo

Acylglycerophosphate acyltransferases (AGPATs) are the rate-limiting enzymes for the de novo pathway of triacylglycerols (TAG) synthesis. Although AGPATs have been extensively explored by evolution, expression and functional studies, little is known on functional characterization of how many members of the AGPAT family are involved in TAG synthesis and their impact on the cell proliferation and apoptosis. Here, 13 AGPAT genes in buffalo were identified, of which 12 AGPAT gene pairs were orthologous between buffalo and cattle. Comparative transcriptomic analysis and real-time quantitative reverse transcription PCR (qRT-PCR) further showed that both AGPAT1 and AGPAT6 were highly expressed in milk samples of buffalo and cattle during lactation. Knockdown of AGPAT1 or AGPAT6 significantly decreased the TAG content of buffalo mammary epithelial cells (BuMECs) and bovine mammary epithelial cells (BoMECs) by regulating lipogenic gene expression (p < 0.05). Knockdown of AGPAT1 or AGPAT6 inhibited proliferation and apoptosis of BuMECs through the expression of marker genes associated with the proliferation and apoptosis (p < 0.05). Our data confirmed that both AGPAT1 and AGPAT6 could regulate TAG synthesis and growth of mammary epithelial cells in buffalo. These findings will have important implications for understanding the role of the AGPAT gene in buffalo milk performance.

miR-556-3p/Disabled Homolog 2-Interacting Protein (dab2ip) Promotes Cancer Progression by Down-Regulating Bcl-2-Like Protein 11 (BIM) Expression in Colorectal Cancer

Colorectal cancer (CRC) is a major threat affecting human health. Studies have shown that miR-556-3p can regulate dab2ip and promote tumor deterioration, and up-regulation of BIM inhibits CRC cell progression. However, the interaction between miR-556-3p/dab2ip and BIM in CRC is unknown. We examined miR-556-3p expression in CRC tissues and cells by RT-qPCR. The impact of miR-556-3p/dab2ip and BIM on CRC cell behaviors were assessed by western blot, transwell and MTT assay. miR-556-3p was highly expressed in CRC and its overexpression increased CRC cell proliferation and migration as well as up-regulated dab2ip and Ki-67 expression. Besides, miR-556-3p could target the BIM and overexpressed miR-556-3p decreased BIM expression. However, silencing of BIM abrogated the impact of overexpressed miR-556-3p on CRC cell proliferation and migration. In conclusion, miR-556-3p/dab2ip promotes cell growth by down-regulating the expression of BIM, thereby promoting the progression of CRC.

Association of p53 with Neurodegeneration in Parkinson's Disease

p53 is a vital transcriptional protein implicated in regulating diverse cellular processes, including cell cycle arrest, DNA repair, mitochondrial metabolism, redox homeostasis, autophagy, senescence, and apoptosis. Recent studies have revealed that p53 levels and activity are substantially increased in affected neurons in cellular and animal models of Parkinson's disease (PD) as well as in the brains of PD patients. p53 activation in response to neurodegenerative stress is closely associated with the degeneration of dopaminergic neurons accompanied by mitochondrial dysfunction, reactive oxygen species (ROS) production, abnormal protein aggregation, and impairment of autophagy, and these pathogenic events have been implicated in the pathogenesis of PD. Pathogenic p53 integrates diverse cellular stresses and activate these downstream events to induce the degeneration of dopaminergic neurons; thus, it plays a crucial role in the pathogenesis of PD and appears to be a potential target for the treatment of the disease. We reviewed the current knowledge concerning p53-dependent neurodegeneration to better understand the underlying mechanisms and provide possible strategies for PD treatment by targeting p53.

Pre-Exposure to Environmental Enrichment Protects against Learning and Memory Deficits Caused by Infrasound Exposure

With the development of industrialization in recent years, infrasound has become an important component of public noise. To date, diverse studies have revealed the negative effects of infrasound on the central nervous system (CNS), especially the learning and memory ability. It is widely reported that environmental enrichment (EE) ameliorates the learning and memory deficits in different models of brain injury. Therefore, the present study was designed to determine the possible benefits of pre-exposure to EE in preventing functional deficits following infrasound exposure and their related mechanism. Adult male rats were given enriched or standard housing for 30 days. Following enrichment, the rats were exposed to 16 Hz, 130 dB infrasound for 14 days, and then their learning and memory ability was assessed. Changes to neuroinflammation, apoptosis, and oxidative stress in the hippocampus were also detected. Our results showed that the infrasound-induced deficit in learning and memory was attenuated significantly in EE pre-exposed rats. Pre-exposure to EE could induce a decrease in proinflammatory cytokines and increased anti-inflammatory cytokines and antioxidant properties in the hippocampus. Moreover, pre-exposure to EE also exerted antiapoptosis functions by upregulating the B-cell lymphoma/leukemia-2 (Bcl-2) level and downregulating the P53 level in the hippocampus. In conclusion, the results of the present study suggested that EE is neuroprotective when applied before infrasound exposure, resulting in an improved learning and memory ability by enhancing antioxidant, anti-inflammatory, and antiapoptosis capacities.

TNFRSF13B is a potential contributor to prostate cancer

Background

Immunodeficiencies are genetic diseases known to predispose an individual to cancer owing to defective immunity towards malignant cells. However, the link between immunodeficiency and prostate cancer progression remains unclear. Therefore, the aim of this study was to evaluate the effects of common genetic variants among eight immunodeficiency pathway-related genes on disease recurrence in prostate cancer patients treated with radical prostatectomy.

Methods

Genetic and bioinformatic analyses on 19 haplotype-tagging single-nucleotide polymorphisms in eight immunodeficiency pathway-related genes were conducted in 458 patients with prostate cancer after receiving radical prostatectomy. Furthermore, the TNFRSF13B was knocked down in 22Rv1 and PC-3 human prostate cancer cell lines via transfecting short hairpin RNAs and cell proliferation and colony formation assays were performed. The molecular mechanisms underlying the effects of TNFRSF13B were further explored by microarray gene expression profiling.

Results

TNFRSF13B rs4792800 was found to be significantly associated with biochemical recurrence even after adjustment for clinical predictors and false discovery rate correction (adjusted hazard ratio 1.78, 95% confidence interval 1.16–2.71, p = 0.008), and the G allele was associated with higher TNFRSF13B expression (p = 0.038). Increased TNFRSF13B expression suggested poor prognosis in four independent prostate cancer datasets. Furthermore, silencing TNFRSF13B expression resulted in decreased colony formation of 22Rv1 and PC-3 cells through modulating the cell cycle and p53 signalling pathways.

Conclusions

The present study suggests the potential role of immunodeficiency pathway-related genes, primarily TNFRSF13B, in prostate cancer progression.

Supplementary information

The online version contains supplementary material available at 10.1186/s12935-022-02590-2.

The CREB and AP-1-Dependent Cell Communication Network Factor 1 Regulates Porcine Epidemic Diarrhea Virus-Induced Cell Apoptosis Inhibiting Virus Replication Through the p53 Pathway

Porcine epidemic diarrhea virus (PEDV) infection causes severe diarrhea, dehydration, and high mortality in sick pigs, causing huge economic losses to the pig industry. However, the relationship between cell communication network factor 1 (CCN1) and PEDV infection has not been reported. In this study, we showed that the expression of CCN1 was enhanced by PEDV infection, and we observed that PEDV promotes the CREB and AP-1 activation to promote CCN1 expression. The PKA and p38 inhibitors significantly suppress CCN1 expression, indicating that PEDV-induced CCN1 expression may be through PKA and p38 pathway. Further tests confirmed that CREB and AP-1 are regulated by PKA and p38, respectively. Overexpression of CCN1 decreased the replication of PEDV, whereas knockdown of CCN1 increased the replication of PEDV. We proved that the overexpression of CCN1 increased the phosphorylation level of p53, promoted the expresion of Bax and the cleavage of caspase 9 and caspase 3, and inhibited the production of Bcl-2. CCN1 knockdown decreased the phosphorylation level of p53, inhibited the production of Bax and the cleavage of caspase 9 and caspase 3, and promoted the expression of Bcl-2. The treatment of PFT-α (p53 inhibitor) significantly suppressed the expression of cleaved caspase 9 and caspase 3, leading to the decrease of apoptosis. Together, these studies showed that PEDV promotes the activation of CREB and AP-1 to increase the expression of CCN1. Overexpression of CCN1 promotes apoptosis by elevating p53 protein phosphorylation and inhibits PEDV replication, and knockdown of CCN1 inhibits apoptosis by decreasing p53 protein phosphorylation and promotes PEDV replication. Our study could provide some reference for the molecular mechanisms of PEDV-induced CCN1 induction and supply a new therapeutic target for PEDV.

Alternative autophagy: mechanisms and roles in different diseases

As an important mechanism to maintain cellular homeostasis, autophagy exerts critical functions via degrading misfolded proteins and damaged organelles. Recent years, alternative autophagy, a new type of autophagy has been revealed, which shares similar morphology with canonical autophagy but is independent of Atg5/Atg7. Investigations on different diseases showed the pivotal role of alternative autophagy during their physio-pathological processes, including heart diseases, neurodegenerative diseases, oncogenesis, inflammatory bowel disease (IBD), and bacterial infection. However, the studies are limited and the precise roles and mechanisms of alternative autophagy are far from clear. It is necessary to review current research on alternative autophagy and get some hint in order to provide new insight for further study. Video Abstract.

The possible involvement of circRNA DMNT1/p53/JAK/STAT in gestational diabetes mellitus and preeclampsia

Circular RNA (circRNA) plays an important role in biological processes of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the mechanisms for circRNA DMNT1 (circ-DMNT1) in GDM and PE remain unclarified. The expression levels of circ-DMNT1 and p53 in GDM and PE were quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis. When the expression of circ-DMNT1 or p53 was abnormal, cell counting kit-8 (CCK-8) assay, bromodeoxyuridine (BrdU) staining, flow cytometry, cell scratch, and Transwell assays were used to assess cell viability, proliferation, cell cycle, apoptosis, migration, and invasion of trophoblast cells, respectively. Subsequently, the binding relationship between circ-DMNT1 and p53 was verified by RNA pull-down and RIP analysis, followed by the determination of JAK/STAT pathway-related protein expression levels using western blot analysis. Both circ-DMNT1 and p53 were highly expressed in GDM and PE. Upregulation of circ-DMNT1 or p53 inhibited trophoblast cell viability, proliferation, migration, and invasion, meanwhile promoting cell apoptosis but blocking cell cycle progression. However, downregulation of circ-DMNT1 or p53 induced trophoblast cell survival. In GDM and PE, circ-DMNT1 activated the JAK/STAT pathway by binding to p53, which resulted in increased expression levels of p-JAK and p-STAT. The results suggested that circ-DMNT1 was involved in the deterioration of GDM and PE, possibly through inducing p53 expression and activating the JAK/STAT signaling pathway.

Circ-LRP1B functions as a competing endogenous RNA to regulate proliferation, apoptosis and oxidative stress of LPS-induced human C28/I2 chondrocytes

Circular RNAs (circRNAs) are crucial for the pathogenesis of human diseases, including osteoarthritis (OA). Here, we set to elucidate the biological action of circ-LRP1B in OA pathogenesis. Human C28/I2 chondrocytes were stimulated by lipopolysaccharide (LPS). Circ-LRP1B, nuclear factor, erythroid 2 like 1 (NRF1) and microRNA (miR)-34a-5p were quantified by quantitative real-time PCR (qRT-PCR) or immunoblotting. Cell viability, proliferation, and apoptosis abilities were gauged by MTT, 5-Ethynyl-2'-Deoxyuridine (EdU) staining, and flow cytometry assays, respectively. Direct relationship between miR-34a-5p and circ-LRP1B or NRF1 was validated by RNA pull-down and dual-luciferase reporter assays. Circ-LRP1B was found to be underexpressed in OA cartilage and LPS-stimulated C28/I2 chondrocytes. Enforced expression of circ-LRP1B promoted cell proliferation, and repressed apoptosis and oxidative stress, as well as impacted OA-specific hallmarks expression of LPS-stimulated C28/I2 cells. NRF1 was identified as a downstream effector of circ-LRP1B function. Moreover, NRF1 was identified as a miR-34a-5p target in LPS-stimulated C28/I2 cells. Circ-LRP1B acted as a competing endogenous RNA (ceRNA) for miR-34a-5p to involve the post-transcriptional regulation of NRF1 expression. Furthermore, the effects of circ-LRP1B overexpression partly depended on the reduction of available miR-34a-5p. These findings demonstrate that circ-LRP1B functions as a ceRNA to regulate the proliferation, apoptosis and oxidative stress of LPS-stimulated human C28/I2 chondrocytes by miR-34a-5p/NRF1 network.

MDM2 is involved in the regulation of p53 expression in the immune response of oyster Crassostrea hongkongensis

MDM2 (mouse double-minute) and p53 form a negative feedback loop and play a prominent role in preventing the induction of uncontrolled apoptosis. To better understand their potential roles in oyster Crassostrea hongkongensis, MDM2 and p53 homologs were first isolated and cloned in C. hongkongensis (named ChMDM2 and Chp53), and their mRNA expression patterns in tissues and developmental stages were analyzed. Multiple sequence alignment analysis and phylogenetic analysis of ChMDM2 and Chp53 displayed a high degree of homology and conservation. In addition, exposure to Vibrio coralliilyticus resulted in DNA damage and apoptosis in the hemocytes of C. hongkongensis, and found that the mRNA expression level of ChMDM2 was decreased, while the relative expression of Chp53 was significantly increased in the hemocytes and gills. Furthermore, fluorescence from ChMDM2-EGFP and Chp53-Red were found to be distributed in the nucleus of HEK293T cells. Besides, dual-luciferase reporter assays showed that ChMDM2 antagonized with Chp53 and participates in p53 signaling pathway. In addition, the interaction between ChMDM2 and Chp53 was confirmed strongly by Co-immunoprecipitation assays. Furthermore, the results of RNAi showed that ChMDM2 and Chp53 participated in apoptosis which induced infection of V. coralliilyticus. Taken together, our results characterized the features of ChMDM2 and Chp53, which played a critical role in apoptosis of C. hongkongensis.

The potential of probiotics in the amelioration of hyperuricemia

Hyperuricemia is a common disease caused by metabolic disorders or the excessive intake of high-purine foods. Persistent hyperuricemia in extreme cases induces gout, and asymptomatic hyperuricemia is probably linked to other metabolic diseases, such as hypertension. The typical damage caused by asymptomatic hyperuricemia includes inflammation, oxidative stress and gut dysbiosis. Probiotics have broad potential applications as food additives, not as drug therapies, in the amelioration of hyperuricemia. In this review, we describe novel methods for potential hyperuricemia amelioration with probiotics. The pathways through which probiotics may ameliorate hyperuricemia are discussed, including the decrease in uric acid production through purine assimilation and XOD (xanthine oxidase) inhibition as well as enhanced excretion of uric acid production by promoting ABCG2 (ATP binding cassette subfamily G member 2) activity, respectively. Three possible probiotic-related therapeutic pathways for alleviating the syndrome of hyperuricemia are also summarized. The first mechanism is to alleviate the oxidation and inflammation induced by hyperuricemia through the inhibition of NLRP3 inflammasome, the second is to restore damaged intestinal epithelium barriers and prevent gut microbiota dysbiosis, and the third is to enhance the innate immune system by increasing the secretion of immunoglobulin A (sIgA) to resist the stimulus by hyperuricemia. We propose that future research should focus on superior strain resource isolation and insight into the cause-effect mechanisms of probiotics for hyperuricemia amelioration. The safety and effects of the application of probiotics in clinical use also need verification.

Loss of RPS27a expression regulates the cell cycle, apoptosis, and proliferation via the RPL11-MDM2-p53 pathway in lung adenocarcinoma cells

Background

Depletion of certain ribosomal proteins induces p53 activation, which is mediated mainly by ribosomal protein L5 (RPL5) and/or ribosomal protein L11 (RPL11). Therefore, RPL5 and RPL11 may link RPs and p53 activation. Thus, this study aimed to explore whether RPs interact with RPL11 and regulate p53 activation in lung adenocarcinoma (LUAD) cells.

Methods

The endogenous RPL11-binding proteins in A549 cells were pulled down through immunoprecipitation and identified with a proteomics approach. Docking analysis and GST-fusion protein assays were used to analyze the interaction of ribosomal protein S27a (RPS27a) and RPL11. Co-immunoprecipitation and in vitro ubiquitination assays were used to detect the effects of knockdown of RPS27a on the interaction between RPS27a and RPL11, and on p53 accumulation. Cell cycle, apoptosis, cell invasion and migration, cell viability and colony-formation assays were performed in the presence of knockdown of RPS27a. The RPS27a mRNA expression in LUAD was analyzed on the basis of the TCGA dataset, and RPS27a expression was detected through immunohistochemistry in LUAD samples. Finally, RPS27a and p53 expression was analyzed through immunohistochemistry in A549 cell xenografts with knockdown of RPS27a.

Results

RPS27a was identified as a novel RPL11 binding protein. GST pull-down assays revealed that RPS27a directly bound RPL11. Knockdown of RPS27a weakened the interaction between RPS27a and RPL11, but enhanced the binding of RPL11 and murine double minute 2 (MDM2), thereby inhibiting the ubiquitination and degradation of p53 by MDM2. Knockdown of RPS27a stabilized p53 in an RPL11-dependent manner and induced cell viability inhibition, cell cycle arrest and apoptosis in a p53-dependent manner in A549 cells. The expression of RPS27a was upregulated in LUAD and correlated with LUAD progression and poorer prognosis. Overexpression of RPS27a correlated with upregulation of p53, MDM2 and RPL11 in LUAD clinical specimens. Knockdown of RPS27a increased p53 activation, thus, suppressing the formation of A549 cell xenografts in nude mice.

Conclusions

RPS27a interacts with RPL11, and RPS27a knockdown enhanced the binding of RPL11 and MDM2, thereby inhibiting MDM2-mediated p53 ubiquitination and degradation; in addition, RPS27a as important roles in LUAD progression and prognosis, and may be a therapeutic target for patients with LUAD.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02230-z.

In silico assessment of DNA damage response gene variants associated with head and neck cancer

Head and neck cancer (HNC), the sixth most common cancer globally, stands first in India, especially Northeast India, where tobacco usage is predominant, which introduces various carcinogens leading to malignancies by accumulating DNA damages. Consequently, the present work aimed to predict the impact of significant germline variants in DNA repair and Tumour Suppressor genes on HNC development. WES in Ion Proton^TM platform on 'discovery set' (n = 15), followed by recurrence assessment of the observed variants on 'confirmation set' (n = 40) using Sanger Sequencing was performed on the HNC-prevalent NE Indian populations. Initially, 53 variants were identified, of which seven HNC-linked DNA damage response gene variants were frequent in the studied populations. Different tools ascertained the biological consequences of these variants, of which the non-coding variants viz. EXO1_rs4150018, RAD52_rs6413436, CHD5_rs2746066, HACE1_rs6918700 showed risk, while FLT3_rs2491227 and BMPR1A_rs7074064 conferred protection against HNC by affecting transcriptional regulation and splicing mechanism. Molecular Dynamics Simulation of the full-length p53 model predicted that the observed coding TP53_rs1042522 variant conferred HNC-risk by altering the structural dynamics of the protein, which displayed difficulty in the transition between active and inactive conformations due to high-energy barrier. Subsequent pathway and gene ontology analysis revealed that EXO1, RAD52 and TP53 variants affected the Double-Strand Break Repair pathway, whereas CHD5 and HACE1 variants inactivated DNA repair cascade, facilitating uncontrolled cell proliferation, impaired apoptosis and malignant transformation. Conversely, FLT3 and BMPR1A variants protected against HNC by controlling tumorigenesis, which requires experimental validation. These findings may serve as prognostic markers for developing preventive measures against HNC.

Simiao Qingwen Baidu decoction inhibits Epstein-Barr virus-induced B lymphoproliferative disease and lytic viral replication

CONTEXT

Simiao Qingwen Baidu decoction (SQBD), a traditional Chinese medicine prescription, can ameliorate Epstein-Barr virus (EBV) induced disease. However, its mechanism still remains unknown.

OBJECTIVE

To detect the mechanism of SQBD in EBV-induced B lymphoproliferative disease in vitro.

MATERIALS AND METHODS

Sprague-Dawley (SD) rats (n = 20) were given SQBD (10 mL/kg) by gavage once a day for 7 d. SQBD-containing serum was obtained from abdominal aortic blood of rats, and diluted with medium to obtain 5%, 10% or 20%-medicated serum. SD rats (n = 10) were given normal saline, and normal serum was collected as a control. EBV-transformed B cells (CGM1) were cultured in medium containing 5%, 10% or 20%-medicated serum. CGM1 cells were treated with normal serum as a control. Cell viability and apoptosis were examined. The expression and activity of proteins were assessed.

RESULTS

We found that IC₅₀ (83 ± 26.07%, 24 h; 69.88 ± 4.69%, 48 h) of 10% medicated serum was higher than that of 5% (25.47 ± 6.98%, 24 h; 21.62 ± 7.30%, 48 h) and 20%-medicated serum (51 ± 7.25%, 24 h; 56.03 ± 2.56%, 48 h). Moreover, SQBD promoted apoptosis of CGM1 cells by regulating EBV latency proteins expression. SQBD inhibited EBV-induced lytic viral replication.

CONCLUSIONS

Our data confirmed that SQBD inhibits EBV-induced B lymphoproliferative disease and lytic viral replication. This work provides a theoretical basis for the mechanism of SQBD in EBV-induced B lymphoproliferative disease, and SQBD may be an effectively therapeutic drug for EBV-induced B lymphoproliferative disease.

Malignant transformation of human bronchial epithelial cells induced by benzo [a] pyrene suggests a negative feedback of TP53 to PPP1R13L via binding a possible enhancer element

Previous studies have shown that PPP1R13L as an inhibitor of apoptosis protease TP53 can lead to abnormal cell proliferation and carcinogenesis, however, the function of PPP1R13L was complicated and the interaction between TP53 and PPP1R13L needs to be further explored. In the present study, a malignant transformation model of human bronchial epithelial cells induced by benzo (a) pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) was established to observe the regulatory patterns between TP53 and PPP1R13L during carcinogenesis. In vitro experiments including CRISPR-Cas9 editing, RNA silence, Co-Immunoprecipitation and Chromatin Immunoprecipitation were applied to discuss their interactive effects. Additionally, TCGA data profile and our clinical samples of lung cancer were also used to analyze their relationship at the transcriptome level. Interestingly, we found that the mRNA and protein level of TP53 and PPP1R13L fluctuated as a wave in BPDE-induced malignant transformation under wild-type TP53 genetic background. Our results have also demonstrated that PPP1R13L acts as an inhibitor of TP53, while TP53 can regulate PPP1R13L via binding a possible enhancer of the first intron of PPP1R13L gene. Likewise, TCGA data and clinical samples have identified that in the case of TP53 mutation, TP53 expression was negatively correlated with PPP1R13L, while in the case of TP53 wild-type, TP53 expression was not correlated with PPP1R13L. It suggested that there existed a negative feedback of wild-type TP53 to PPP1R13L, which reminded a unique implication during chemical carcinogenesis.

Zearalenone exposure mediated hepatotoxicity via mitochondrial apoptotic and autophagy pathways: Associated with gut microbiome and metabolites

Zearalenone (ZEN), a mycotoxin is frequently detected in different food products and has been widely studied for its toxicity. However, the underlying mechanisms of hepatotoxic effects, relationship between gut microbiome and liver metabolite mediated hepatotoxicity mechanisms induced by ZEN are still not clear. Here, we reported that the different microscopic changes like swelling of hepatocyte, disorganization of hepatocytes and extensive vacuolar degeneration were observed, and the mitochondrial functions decreased in exposed mice. Results exhibited up-regulation in expression of signals of apoptosis and autophagy in liver of treated mice via mitochondrial apoptotic and autophagy pathway (Beclin1/p62). The diversity of gut microbiome decreased and the values of various microbiome altered in treated mice, including 5 phyla (Chloroflexi, Sva0485, Methylomirabilota, MBNT15 and Kryptonia) and genera (Frankia, Lactococcus, Anaerolinea, Halomonas and Sh765B-TzT-35) significantly changed. Liver metabolism showed that the concentrations of 91 metabolite including lipids and lipid like molecules were significantly changed. The values of phosphatidylcholine, 2-Lysophosphatidylcholine and phosphatidate concentrations suggestive of abnormal glycerophosphate metabolism pathway were significantly increased in mice due to exposure to ZEN. In conclusion, the findings suggest that the disorders in gut microbiome and liver metabolites due to exposure to ZEN in mice may affect the liver.

Pleiotropin enhances the osteo/dentinogenic differentiation potential of dental pulp stem cells

Purpose: Pleiotrophin (PTN) is a heparin-binding growth-associated molecule and expressed in ameloblasts and odontoblasts throughout tooth maturation. Our previous study has shown that PTN expressed more than 20-fold higher in dental tissue than dental stem cells. However, the role of PTN on proliferation and osteo/dentinogenesis of dental pulp stem cells (DPSCs) is unclear. The purpose of the present study was to investigate the role of PTN on the DPSCs' function.Methods: DPSCs were isolated from human third molars. Short hairpin RNAs (shRNAs) was used to knock down the PTN expression in DPSCs. Real-time RT-PCR, alizarin red staining, quantitative calcium analysis, in vivo transplantation and cell counting kit-8 (CCK8) assay were used to study the function of DPSCs. Possible mechanism was studied by RNA sequencing.Results: After PTN depletion, ALP activity and mineralization ability of DPSCs decreased. Expression of DMP-1 and BSP weakened. Proliferation of DPSCs at 48 h and 72 h was inhibited. Furthermore, 50 pg/mL PTN recombinant protein rescued the impaired osteo/dentinogenic differentiation potential and proliferation ability caused by PTN depletion. In addition, RNA sequencing showed 221 genes were downregulated and 233 genes upregulated in PTN depleted DPSCs. Several genes including BMP2 and IGFBP5 might be associated with PTN function on the DPSCs. P53 and the AMPK signaling pathways were involved. LncRNA analysis displayed 47 significantly upregulated lncRNA and 31 downregulated lncRNA comparing PTN depleted DPSCs with the control.Conclusion: Our research demonstrated that PTN has a positive role in maintaining DPSCs proliferation and osteo/dentinogenic differentiation potential.

TCF19 and p53 regulate transcription of TIGAR and SCO2 in HCC for mitochondrial energy metabolism and stress adaptation

Alteration in glucose homeostasis during cancer metabolism is an important phenomenon. Though several important transcription factors have been well studied in the context of the regulation of metabolic gene expression, the role of epigenetic readers in this regard remains still elusive. Epigenetic reader protein transcription factor 19 (TCF19) has been recently identified as a novel glucose and insulin-responsive factor that modulates histone posttranslational modifications to regulate glucose homeostasis in hepatocytes. Here we report that TCF19 interacts with a non-histone, well-known tumor suppressor protein 53 (p53) and co-regulates a wide array of metabolic genes. Among these, the p53-responsive carbohydrate metabolic genes Tp53-induced glycolysis and apoptosis regulator (TIGAR) and Cytochrome C Oxidase assembly protein 2 (SCO2), which are the key regulators of glycolysis and oxidative phosphorylation respectively, are under direct regulation of TCF19. Remarkably, TCF19 can form different transcription activation/repression complexes which show substantial overlap with that of p53, depending on glucose-mediated variant stress situations as obtained from IP/MS studies. Interestingly, we observed that TCF19/p53 complexes either have CBP or HDAC1 to epigenetically program the expression of TIGAR and SCO2 genes depending on short-term high glucose or prolonged high glucose conditions. TCF19 or p53 knockdown significantly altered the cellular lactate production and led to increased extracellular acidification rate. Similarly, OCR and cellular ATP production were reduced and mitochondrial membrane potential was compromised upon depletion of TCF19 or p53. Subsequently, through RNA-Seq analysis from patients with hepatocellular carcinoma, we observed that TCF19/p53-mediated metabolic regulation is fundamental for sustenance of cancer cells. Together the study proposes that TCF19/p53 complexes can regulate metabolic gene expression programs responsible for mitochondrial energy homeostasis and stress adaptation.

MYC: a multipurpose oncogene with prognostic and therapeutic implications in blood malignancies

MYC oncogene is a transcription factor with a wide array of functions affecting cellular activities such as cell cycle, apoptosis, DNA damage response, and hematopoiesis. Due to the multi-functionality of MYC, its expression is regulated at multiple levels. Deregulation of this oncogene can give rise to a variety of cancers. In this review, MYC regulation and the mechanisms by which MYC adjusts cellular functions and its implication in hematologic malignancies are summarized. Further, we also discuss potential inhibitors of MYC that could be beneficial for treating hematologic malignancies.

Oridonin improves the therapeutic effect of lentinan on lung cancer

Oridonin, a compound from Rabdosia rubescens, has been shown to exhibit a potent ability to improve the antitumor effects of lentinan (LNT). In the present study, the effects of oridonin, LNT, and the combination of these treatments were assessed on the normal human fetal lung fibroblast cell line MRC-5, as well as the non-small cell lung cancer cell line A549. Next, their effects on metastasis and survival in vivo were assessed in a mouse model of lung cancer. The effects of the treatments on the mRNA and protein expression levels of several regulatory factors in A549 cells and lung tissues were determined using reverse transcription-quantitative PCR and western blotting. The results showed that the viability of MRC-5 and A549 cells were not affected by 0-20 µg/ml oridonin; 0-300 µg/ml LNT did not affect the viability of MRC-5 cells, but 50-400 µg/ml LNT reduced the viability of A549 cells. Thus, 20 µg/ml oridonin and 100 or 300 µg/ml LNT were used in the subsequent experiments. Treatment with oridonin and LNT, alone or combined, had no effect on MRC-5 cell viability. Oridonin treatment had no effect on A549 cell viability; however, LNT suppressed A549 cell viability, and oridonin promoted the suppressive effects of LNT on A549 cells. In vivo analysis showed that oridonin alone had no effect on metastasis and survival, but LNT decreased metastasis and survival in mice. Oridonin augmented the effects of LNT against metastasis and further improved the survival rates of mice. In both A549 cells and lung tissues, LNT increased the mRNA and protein expression levels of caspase-3, caspase-8, caspase-9, Bax, p53, p21 and inhibitor of nuclear factor-κB (NF-κB)-α, and reduced the mRNA and protein expression levels of Bcl-2 and NF-κB. Oridonin augmented all the effects of LNT on expression of these proteins in the cells. Together, the results showed that oridonin enhanced the antitumor effects of LNT, and may thus serve as an adjuvant alongside LNT as a novel anticancer regimen for treatment of lung cancer.

Krϋppel-like factor 15 suppresses renal glomerular mesangial cell proliferation via enhancing P53 SUMO1 conjugation

Mesangial cell (MC) proliferation is a key pathological feature in a number of common human renal diseases, including mesangial proliferative nephritis and diabetic nephropathies. Knowledge of MC responses to pathological stimuli is crucial to the understanding of these disease processes. We previously determined that Krϋppel‐like factor 15 (KLF15), a kidney‐enriched zinc‐finger transcription factor, was required for inhibition of MC proliferation. In the present study, we investigated the direct target gene and the underlying mechanism by which KLF15 regulated mesangial proliferation. First, we screened small ubiquitin‐related modifier 1 (SUMO1) as the direct transcriptional target of KLF15 and validated this finding with ChIP‐PCR and luciferase assays. Furthermore, we demonstrated that overexpressing KLF15 or SUMO1 enhanced the stability of P53, which blocked the cell cycle of human renal MCs (HRMCs) and therefore abolished cell proliferation. Conversely, knockdown of SUMO1 in HRMCs, even those overexpressed with KLF15, could not inhibit HRMC proliferation rates and increase SUMOylation of P53. Finally, the results showed that the levels of SUMOylated P53 in the kidney cortices of anti‐Thy 1 model rats were decreased during proliferation periods. These findings reveal the critical mechanism by which KLF15 targets SUMO1 to mediate the proliferation of MCs.

7-Difluoromethoxy-5,4'-dimethoxy-genistein attenuates macrophages apoptosis to promote plaque stability via TIPE2/TLR4 axis in high fat diet-fed ApoE-/- mice

Promoting plaque stability is of great significance for prevention and treatment of cardiovascular diseases. 7-difluoromethoxy-5,4'-dimethoxygenistein (DFMG) is a novel active compound synthesized using genistein, which exerts anti-atherosclerotic effect. In this study, we evaluated effects of DFMG on plaque stability in ApoE^-/- mice fed with high fat diet (HFD), and explored the molecular mechanism by using ApoE^-/-TLR4^-/- mice and RAW264.7 cells. Here, we found that DFMG significantly reduced plaque areas, macrophages infiltration and apoptosis, and TLR4 expression in HFD-fed ApoE^-/- mice. Meanwhile, DFMG increased collagen fibers, smooth muscle cells and TIPE2 expression in plaques and media. Besides, TLR4 knockout promoted the protective effects of DFMG on plaques. In vitro, DFMG decreased lysophosphatidylcholine (LPC)-induced macrophages apoptosis and TLR4, while upregulated TIPE2. Moreover, TIPE2 reduced TLR4, MyD88, p-NF-κB p65^Ser276, cleaved Caspase-3 overproduction, and enhanced effects of DFMG on LPC-induced macrophages. Overall, our study demonstrates that DFMG can promote plaque stability by reducing macrophage apoptosis through TIPE2/TLR4 signaling pathway, which suggests DFMG should be used to develop food additives or drugs for preventing atherosclerosis.

EZH2-miRNA Positive Feedback Promotes Tumor Growth in Ovarian Cancer

Enhancer of zester homolog 2 (EZH2), a histone methyl transferase that mediates H3K27me3 through polycomb repressive complex 2 (PRC2), is overexpressed in ovarian cancer and promotes malignant proliferation. However, the underlying mechanism of maintaining high EZH2 expression remains elusive. Here we showed that microRNA(miRNA) inhibited EZH2 by binding to the 3′-UTR of EZH2 mRNA; conversely, EZH2 can inhibit miRNA expression. We confirmed that a feedback loop exists between EZH2 and miRNA that maintained EZH2 overexpression, thus promoting ovarian cancer proliferation in vivo and in vitro. We further explored that EZH2 inhibited miRNA expression through PRC2, as determined by CHIP (chromatin immunoprecipitation), and EZH2 decreased the expression of p21, p53, and RUNX3. These results suggest that EZH2 inhibits the expression of Et-miRNAs (EZH2-targeting miRNAs) through the H3K27me3 pathway, thus forming an EZH2-miRNA positive feedback loop that maintains the high expression of EZH2 and promotes the malignant proliferation of cancer cells by regulating the expression of cell proliferation-related proteins.

iASPP protects the heart from ischemia injury by inhibiting p53 expression and cardiomyocyte apoptosis

Currently, there remains a great need to elucidate the molecular mechanism of acute myocardial infarction in order to facilitate the development of novel therapy. Inhibitor of apoptosis-stimulating protein of p53 (iASPP) is a member of the ASPP family proteins and an evolutionarily preserved inhibitor of p53 that is involved in many cellular processes, including apoptosis of cancer cells. The purpose of this study was to investigate the possible role of iASPP in acute myocardial infarction. The protein level of iASPP was markedly reduced in the ischemic hearts in vivo and hydrogen peroxide-exposed cardiomyocytes in vitro. Overexpression of iASPP reduced the infarct size and cardiomyocyte apoptosis of mice subjected to 24 h of coronary artery ligation. Echocardiography showed that cardiac function was improved as indicated by the increase in ejection fraction and fractional shortening. In contrast, knockdown of iASPP exacerbated cardiac injury as manifested by impaired cardiac function, increased infarct size, and apoptosis rate. Mechanistically, overexpression of iASPP inhibited, while knockdown of iASPP increased the expressions of p53 and Bax, the key regulators of apoptosis. Taken together, our results suggested that iASPP is an important regulator of cardiomyocyte apoptosis, which represents a potential target in the therapy of myocardial infarction.

Orchestrated efforts on host network hijacking: Processes governing virus replication

With the high pervasiveness of viral diseases, the battle against viruses has never ceased. Here we discuss five cellular processes, namely "autophagy", "programmed cell death", "immune response", "cell cycle alteration", and "lipid metabolic reprogramming", that considerably guide viral replication after host infection in an orchestrated manner. On viral infection, "autophagy" and "programmed cell death" are two dynamically synchronized cell survival programs; "immune response" is a cell defense program typically suppressed by viruses; "cell cycle alteration" and "lipid metabolic reprogramming" are two altered cell housekeeping programs tunable in both directions. We emphasize on their functionalities in modulating viral replication, strategies viruses have evolved to tune these processes for their benefit, and how these processes orchestrate and govern cell fate upon viral infection. Understanding how viruses hijack host networks has both academic and industrial values in providing insights toward therapeutic strategy design for viral disease control, offering useful information in applications that aim to use viral vectors to improve human health such as gene therapy, and providing guidelines to maximize viral particle yield for improved vaccine production at a reduced cost.

Transcriptomic Analysis of Naïve Human Embryonic Stem Cells Cultured in Three-Dimensional PEG Scaffolds

Naïve human embryonic stem cells (ESCs) are characterized by improved viability, proliferation, and differentiation capacity in comparison to traditionally derived primed human ESCs. However, currently used two-dimensional (2-D) cell culture techniques fail to mimic the three-dimensional (3-D) in vivo microenvironment, altering morphological and molecular characteristics of ESCs. Here, we describe the use of 3-D self-assembling scaffolds that support growth and maintenance of the naïve state characteristics of ESC line, Elf1. Scaffolds were formed via a Michael addition reaction upon the combination of two 8-arm polyethylene glycol (PEG) polymers functionalized with thiol (PEG-8-SH) and acrylate (PEG-8-Acr) end groups. 3-D scaffold environment maintained the naïve state and supported the long-term growth of ESCs. RNA-sequencing demonstrated significant changes in gene expression profiles between 2-D and 3-D grown cells. Gene ontology analysis revealed upregulation of biological processes involved in the regulation of transcription and translation, extracellular matrix organization, and chromatin remodeling in 3-D grown cells. 3-D culture conditions also induced upregulation of genes associated with Wnt and focal adhesion signaling, while p53 signaling pathway associated genes were downregulated. Our findings, for the first time, provide insight into the possible mechanisms of self-renewal of naïve ESCs stimulated by the transduction of mechanical signals from the 3-D microenvironment.

High-expression of ROCK1 modulates the apoptosis of lens epithelial cells in age-related cataracts by targeting p53 gene

Background

Age-related cataract (ARC) is a serious visual impairment disease, and its pathogenesis is unclear. This article aims to investigate the role of ROCK1 in the apoptosis of lens epithelial cells (LECs) in age-related cataracts.

Methods

We collect anterior capsule samples from normal people, patients with age-related cataracts, young mice and naturally aging cataract mice. The oxidative stress-induced apoptosis model was constructed by cultivating HLE-B3 cells with H₂O₂. MTT, Hoechst 33342, and TUNEL assay were performed to explore proliferation and apoptosis. HE assay was used to observe cell morphology. The gene and protein expression were assessed by quantitative real-time PCR, western blot, immunofluorescence, and immunohistochemical staining.

Result

The results from the clinic and mice experiments showed that the numbers of lens epithelial cells from cataract individuals were less than the control individuals. In vitro, the apoptotic cells were increased in lens epithelial cells under H₂O₂ treatment. The ROCK1 protein level increased in the lens epithelial cells from age-related cataract patients and the old mice, respectively. Meanwhile, the up-regulation of the ROCK1 gene was associated with H₂O₂-induced HLE-B3 cells apoptosis. MTT and apoptosis assay showed ROCK1 was necessary in mediating H₂O₂-induced lens epithelial cells apoptosis through ROCK1 over-expression and knockdown experiment, respectively. Further investigation showed that p53 protein levels had been increased during ROCK1-mediated apoptosis in response to H₂O₂. Besides, ROCK1 phosphorylated p53 at ser15 to up-regulate its protein level.

Conclusions

This study established the novel association of ROCK1/p53 signaling with lens epithelial cells apoptosis and age-related cataract genesis.

Lead and cadmium exposure induces male reproductive dysfunction by modulating the expression profiles of apoptotic and survival signal proteins in tea-garden workers

The aim of this study was to evaluate the impact of Lead (Pb) and Cadmium (Cd) exposure at the molecular level on the reproductive status of tea garden workers in North-East India. Using semen samples, we experimentally determined sperm analysis as well as oxidative stress parameters in all samples and evaluated the expression levels of apoptotic and cell survival proteins [p53, phospho-Akt, nuclear factor-κB (NF-κB, p50 subunit) and B cell lymphoma 2 (Bcl2)]. Our data revealed significant differences in the average heavy metal concentrations and various semen analysis profile between the infertile and normal groups. Increasing Pb and Cd concentrations in semen samples of patients showed positive associations with increasing number of multiple defects in sperm and the level of seminal oxidative stress markers in the high Pb and Cd concentration groups. These groups also exhibited positive correlations between high metal concentrations and the average p53 expression levels, but negative correlations with the mean p-Akt cascade protein levels in sperm cells. In the low Pb and Cd concentrations groups, we also observed reverse mean range and correlation patterns. Therefore, our findings may suggest that graded levels of metal exposure significantly influence the relative fluctuation in the levels of p53 and Akt cascade proteins in the sperm cells of infertile subjects. Furthermore, this may be a regulating factor of sperm cell fate, in turn, determining the fertility outcome of the men working in the tea gardens.

Skin photo-protection with phytochemicals against photo-oxidative stress, photo-carcinogenesis, signal transduction pathways and extracellular matrix remodeling-An overview

Excessive exposure of skin to UV radiation triggers the generation of oxidative stress, inflammation, immunosuppression, apoptosis, matrix-metalloproteases production, and DNA mutations leading to the onset of photo ageing and photo-carcinogenesis. At the molecular level, these changes occur via activation of several protein kinases as well as transcription pathways, formation of reactive oxygen species, and release of cytokines, interleukins and prostaglandins together. Current therapies available on the market only provide limited solutions and exhibit several side effects. The present paper provides insight into scientific studies that have elucidated the positive role of phytochemicals in counteracting the UV-induced depletion of antioxidant enzymes, increased lipid peroxidation, inflammation, DNA mutations, increased senescence, dysfunctional apoptosis and immune suppression. The contribution of phytochemicals to the downregulation of expression of oxidative-stress sensitive transcription factors (Nrf2, NF-Kb, AP-1 and p53) and protein kinases (MSK, ERK, JNK, p38 MAPK, p90RSK2 and CaMKs) involved in inflammation, apoptosis, immune suppression, extracellular matrix remodelling, senescence, photo ageing and photo-carcinogenesis, is also discussed. Conclusively, several phytochemicals hold potential for the development of a viable solution against UV irradiation-mediated photo ageing, photo-carcinogenesis and related manifestations.